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HTML 

              
                <h1>
  Implementing Masonry layout with just display grid
</h1>
<p>
  It is possible to implement a masonry layout with existing grid layout as long as one constraint is satisfied.
</p>
<p>
  <strong>
    We need to know the height of each element in the layout in advance.
  </strong>
</p>
<p>
  In practice this means that either the heights of the cards are static regardless of the width of the cards. OR. the width of the columns is static and so the height of the cards is static and known ahead of time as well.
</p>
<p>
  Pinterest meets both these requirements. They have an adaptive number of columns, but the width of the columns is fixed. Also, they must
  know the dimensions of the images they render ahead of time.
</p>
<p>
  The idea is simply that the rows in the grid are defined to be an arbitrary height using "grid-auto-rows". In this example, I chose 10px, which means that every card can have a height which is a multiple of 20px, but it is possible to use any level accuracy needed. We could use 1px instead of 20.
</p>
<p>
  Next, when setting the height of the cards, we also set "grid-row: span (number)" where the number is chosen based on the height of the card PLUS whatever margin you need below the card. Gap would be applied between all rows and would mess up the math, so it is important to keep row-gap to 0. Finally, some negative margin at the bottom fixes up the gaps.
</p>
<p>
  The result is an adaptive masonry layout that automatically fills gaps and rearranges as needed. The cards are not rearranged too much are generally in left-to-right and top-to-bottom order.
</p>




<div class="grid">
  <div class="item" style="--s: 17">1</div>
  <div class="item" style="--s: 12">2</div>
  <div class="item" style="--s: 6">3</div>
  <div class="item" style="--s: 18">4</div>
  <div class="item" style="--s: 8">5</div>
  <div class="item" style="--s: 12">6</div>
  <div class="item" style="--s: 24">7</div>
  <div class="item" style="--s: 4">8</div>
  <div class="item" style="--s: 8">9</div>
  <div class="item" style="--s: 8">10</div>
  <div class="item" style="--s: 7">11</div>
  <div class="item" style="--s: 17">12</div>
  <div class="item" style="--s: 5">13</div>
  <div class="item" style="--s: 6">14</div>
  <div class="item" style="--s: 13">15</div>
  <div class="item" style="--s: 12">16</div>
  <div class="item" style="--s: 12">17</div>
  <div class="item" style="--s: 6">18</div>
  <div class="item" style="--s: 22">19</div>
  <div class="item" style="--s: 20">20</div>
  <div class="item" style="--s: 15">21</div>
  <div class="item" style="--s: 24">22</div>
  <div class="item" style="--s: 15">23</div>
  <div class="item" style="--s: 17">24</div>
  <div class="item" style="--s: 10">25</div>
  <div class="item" style="--s: 13">26</div>
  <div class="item" style="--s: 16">27</div>
  <div class="item" style="--s: 9">28</div>
  <div class="item" style="--s: 4">29</div>
  <div class="item" style="--s: 10">30</div>
  <div class="item" style="--s: 23">31</div>
  <div class="item" style="--s: 13">32</div>
  <div class="item" style="--s: 4">33</div>
  <div class="item" style="--s: 15">34</div>
  <div class="item" style="--s: 8">35</div>
  <div class="item" style="--s: 14">36</div>
  <div class="item" style="--s: 17">37</div>
  <div class="item" style="--s: 24">38</div>
  <div class="item" style="--s: 6">39</div>
  <div class="item" style="--s: 9">40</div>
  <div class="item" style="--s: 5">41</div>
  <div class="item" style="--s: 6">42</div>
  <div class="item" style="--s: 17">43</div>
  <div class="item" style="--s: 4">44</div>
  <div class="item" style="--s: 12">45</div>
  <div class="item" style="--s: 6">46</div>
  <div class="item" style="--s: 10">47</div>
  <div class="item" style="--s: 7">48</div>
</div>
!

CSS 

              
                .grid {
  display: grid;
  /*
    NOTE: This example uses a granularity of 20px.
    i.e. each card can only be a multiple 20px tall.
    However, we can increase the granularily by decreasing this value
    to as low as 1px.
    I assume, using 20x the grid rows of 1px height each would
    create some performance issues, and so I think it's best to
    choose the largest number you can get away with.
  */
  grid-auto-rows: 20px;
  grid-template-columns: repeat(auto-fill, 160px);
  /*
    NOTE: although row-gap is not usable, column-gap is.
  */
  column-gap: 20px;
  justify-content: center;
  margin-bottom: -20px;
  margin-top: 100px;
}

.item {
  background-color: red;
  width: 100%;
  height: calc(var(--s) * 20px);
  /* 
    NOTE: Notice the +1
    That leaves 1 row (i.e. 20px) of extra space below each card.
    (The height is --s rows tall, but it takes up --s + 1 rows of space)
      
    This is used instead of `row-gap` as having row gaps would
    mess up the `span` math.
  */
  grid-row: span calc(var(--s) + 1);
  border-radius: 8px;
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: system-ui;
  font-size: 2rem;
  /* Just some random colors for the cards */
  &:nth-child(12n + 1) { background-color: red; }
  &:nth-child(12n + 2) { background-color: hotpink; }
  &:nth-child(12n + 3) { background-color: rebeccapurple; }
  &:nth-child(12n + 4) { background-color: orange; }
  &:nth-child(12n + 5) { background-color: green; }
  &:nth-child(12n + 6) { background-color: lime; color: black; }
  &:nth-child(12n + 7) { background-color: aqua; color: black; }
  &:nth-child(12n + 8) { background-color: yellow; color: black; }
  &:nth-child(12n + 9) { background-color: grey; }
  &:nth-child(12n + 10) { background-color: black; }
  &:nth-child(12n + 11) { background-color: blue; }
  &:nth-child(12n + 12) { background-color: brown; }
}

h1, p {
  font-family: system-ui;
  max-width: 60rem;
  padding-inline: 2rem;
  margin-inline: auto;
}
!

JS
!
999px

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